如何在鼠标进入另一个JPanel时更改JPanel的背景颜色

Question

我对Java Swing还不熟悉，这是我的第一个问题，所以请原谅我的错误。我正在尝试制作一个具有GridBagLayout的JPanel（容器），并容纳许多较小的JPanel，它们将用作按钮。我为每个小JPanel设置了一个mouseEntered监听器，用于更改背景颜色。

是否可能同时更改该面板所在行和列的颜色？例如，如果我将鼠标移动到单元格(4,3)，我希望单元格(4,0)和(0,3)的背景也会更改。

以下是我的Container：

public class CellPane extends JPanel{

   private List<Cell> cellList;
   private final GridBagConstraints gbc;
   private Cell cell;
   private int counter;

   public CellPane(){

     this.setLayout(new GridBagLayout()); 
     gbc = new GridBagConstraints();
     cellList = new ArrayList<>();
     counter = 0;
        for(int row=0;row<15;row++)
            for(int col=0;col<31;col++){
                gbc.gridx = col;
                gbc.gridy = row;

                cell = new Cell(col ,row);

                Border border = null;
                if (row < 14) {
                    if (col < 30) {
                        border = new MatteBorder(1, 1, 0, 0, new Color(153,204,204));
                    } else {
                        border = new MatteBorder(1, 1, 0, 1, new Color(153,204,204));
                    }
                } else {
                    if (col < 30) {
                        border = new MatteBorder(1, 1, 1, 0, new Color(153,204,204));
                    } else {
                        border = new MatteBorder(1, 1, 1, 1, new Color(153,204,204));
                    }
                }

                cell.setBorder(border);
                cellList.add(counter, cell);
                counter++;
                this.add(cell,gbc);                   
            }  
        System.out.println("Count: " + this.getComponentCount());
        for(Cell c: cellList){
            System.out.println(c.getCellCol()+" "+c.getCellRow());
        }
   }

   public List getCellList(){
       return cellList;
   }
   public int getCellCount(){
       return counter;
   }}

以下是Cell类

class Cell extends JPanel implements MouseListener, PropertyChangeListener{

    private final Color defaultBackground = new Color(240,240,240);
    private final Color clickedColor = new Color(204,0,102);
    private final Color movingColor = new Color(153,255,153);
    private final int row ,col;
    //private CellPane cp = new CellPane();

    public Cell(int x, int y) {
      this.col = x;
      this.row = y;

      if (col>0 & row>0){
        addMouseListener(this);           
      }
      if(col==0 | row == 0){
          addPropertyChangeListener(this);
      }
      if (col == 0){
          this.setPreferredSize(new Dimension(100,35));
      }
      else{
          this.setPreferredSize(new Dimension(35,35));
      }
    }

@Override
public void mouseClicked(MouseEvent me) {
}

@Override
public void mousePressed(MouseEvent me) {
    if(col>0 & row>0 & this.getBackground().equals(movingColor)){
        this.setBackground(clickedColor);        
    }
    else if(this.getBackground().equals(clickedColor)){
        this.setBackground(defaultBackground);
    }
}

@Override
public void mouseReleased(MouseEvent me) {
}

@Override
public void mouseEntered(MouseEvent me) {
    if(col>0 & row>0 & this.getBackground().equals(defaultBackground)){
        this.setBackground(movingColor);
        System.out.println("You clicked on: " + col +" " +row);
        System.out.println("List Size:  " );
    }       
}

@Override
public void mouseExited(MouseEvent me) {
    if(col>0 & row>0 & this.getBackground().equals(movingColor)){
        this.setBackground(defaultBackground);        
    }       
}

@Override
public void propertyChange(PropertyChangeEvent pce) {

}

public int getCellCol(){
    return this.col;
}
public int getCellRow(){
    return this.row;
}}

这里是主要的类

public class ScheduleForm {

private JFrame mainFrame;
private JPanel pnlButtons;
private JPanel pnlCalendar;
private CellPane cellPane;


    public ScheduleForm(){
        initButtonPanel();
        initCalendarPane();
        initFrame();
    }                    

    private void initCalendarPane(){
       pnlCalendar = new JPanel(new BorderLayout());
       pnlCalendar.setPreferredSize(new Dimension(100,500));
       pnlCalendar.setBorder(BorderFactory.createLineBorder(Color.ORANGE));
       cellPane = new CellPane();
       pnlCalendar.add(cellPane,BorderLayout.CENTER);
    }

    private void initButtonPanel(){
       pnlButtons = new JPanel(new BorderLayout());
       pnlButtons.setPreferredSize(new Dimension(100,100));
       pnlButtons.setBorder(BorderFactory.createTitledBorder("Buttons"));  
            }

    private void initFrame(){                                            
       mainFrame = new JFrame("Schedule");
       mainFrame.setLayout(new BorderLayout());
       mainFrame.add(pnlButtons, BorderLayout.NORTH);
       mainFrame.add(pnlCalendar,BorderLayout.CENTER);
       mainFrame.pack();
       mainFrame.setLocationRelativeTo(mainFrame);
       mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
       mainFrame.setVisible(true);
       mainFrame.setExtendedState(java.awt.Frame.MAXIMIZED_BOTH);                
    }

    public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(PopTest.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        @Override
        public void run() {                                
            try {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
            } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
            }
            ////EDW tha mpei to neo antikeimeno
            ScheduleForm scheduleForm = new ScheduleForm();
        }
    });
}}

- Kostas

---

你可以创建一个二维数组并将所有单元格存储在其中。(然后只需调用 array[row][col].setBackground(...) ) - Lukas Rotter

你能再具体一点吗？因为我已经将单元格存储在列表中了，但我不知道如何从容器类中获取该列表并在enterMouseListener中使用它。或者我的逻辑完全偏离了主题？ - Kostas

请告诉我我的回答是否有意义，或者如果您对此有任何问题，请告诉我。 - Hovercraft Full Of Eels

Answer 1

可能的解决方案：

1. 为单元格提供公共方法，允许外部类更改背景颜色状态。
2. 在单元格的MouseListener中，当鼠标进入或离开时触发属性更改。
3. 如果使用推荐的干净MVC模式，则使您的模型侦听这些更改并通知视图更改，以便行和列的颜色可以更改。
4. 如果不使用干净的MVC而是使用快速且简单的GUI，则将CellPane添加到Cells的PropertyChangeListener中，以便它被通知关于鼠标进入/离开的单个Cell状态更改，然后CellPane可以通过调用上述第1点中的公共方法来更改行和列颜色。

- Hovercraft Full Of Eels

---

由于我不熟悉MVC（但打算学习），所以我使用了第四种解决方案。非常感谢。 - Kostas